I've wanted to do this for some time now, and with the new SMa mods now available for the smaller SM transmitters it seems now is the time. I'm upgrading all my UM transmitters to the SMa model. It's an expensive transition, but the size, weight and performance benefit makes it a worthwhile expense. The boom rigs will stay as UM's but I am upgrading to the UM450, 1/4 watt version.
I'll report later on the transition.
We start Swingtown at the end of the month, so it's clean up and upgrade time.